Elliptic spring



Aug. 29, 1939. w. H. BASELT ELLIPTIG SPRING Filed May 20, 1938 INVENTOK I W HBweZZ,

ATTORNEY.

Patented Aug. 29, 1939 PATENT OFFICE ELLIPTIO SPRING Walter H. Baselt, Chicago, Ill., assignor to American Steel Foundries, Chicago, 111., a corporation of New Jersey Application May 20, 1938, Serial No. 208,970

12 Claims.

My invention relates to elliptic springs of the type generally designated full elliptics.

In such springs it is a common practice to assemble the top and bottom halves of the spring each as a unit in the form of a semi-elliptic spring and later to assemble the two halves by mounting their ends in what are usually called end castings.

The end castings are commonly designed to receive the turned-over ends or lips of the springs of the top and bottom halves, said lips being depended upon by cooperation with said castings to retain the parts of the spring in assembly.

Under ordinary conditions of design and loading the usual arrangement above described is satisfactory. However, conditions sometimes require the use of a full elliptic spring which is to be subjected to a maximum load of approximately twice that of the normal load and to obtain satisfactory riding performance under both normal and maximum load conditions, Special end castings are necessary. As the load on the spring increases these special end castings serve to shorten the effective spring length, thereby increasing its stiffness and load-carrying capacity. Under such circumstances difficulties arise in maintaining the parts of the full elliptic spring in assembly, particularly where such usage is in a service where the springs are subjected to heavy shocks such as in railway rolling stock.

An object of my invention is to design a full elliptic spring of the variable length type wherein the top and bottom halves are retained in as- V sembled relationship by end castings and where- 35 in a spring arrangement of the top and bottom springs in cooperation with said end casting is effective to preventaccidental dismantling of the parts under the most extreme conditions of loading or shock.

An embodiment of my invention is shown in the accompanying drawing wherein Figure 1 is a top plan view of one form of full elliptic spring;

Figure 2 is a side elevation thereof;

Figure 3 is an enlarged plan view of the end casting used in the spring shown in Figures 1 and 2;

Figure 4 is an enlarged sectional view through the spring structure shown in Figures' 1 and 2, 50 the section being taken substantially in the plane indicated by the line 44 of Figure 1;

Figure 5 is a top plan view of one of the leaves of said elliptic spring which cooperates with the end castings; Figure 6 is a side elevation and Figure '7 is an end view thereof; and

Figure 8 is a top plan view of a modified form of leaf corresponding to the leaves shown in Figures 5, 6 and 7.

Describing my novel structure in more detail, the spring generally designated 2 comprises the upper half or portion consisting of three units designated respectively 4, 6 and 8, each composed of a series of leaves of graduated length, all of said units being secured in a single assembly by means of the center band ID. The bottom half of the spring designated I2 is similarly formed of three units secured in a like manner by the band 14. The longest leaf of each unit, whether of the top or bottom half, is of identical form and shape and designated by the numeral iii, the detail structure of said longest leaves being shown in Figures 5, 6 and 7. The top and bottom halves of the spring are maintained in assembled relationship by the end castings i8 and 20, the detail structure of which is shown in Figures 3 and 4.

From a consideration of Figures 5, 6 and '7 it will be apparent that in my novel form of spring I have provided each of the longest leaves l6 with a novel structure at each end comprising the in-turned lip 22, said in-turned lip extending across approximately half the width of the leaf as best seen from a consideration of Figures 5 and '7. In the modification shown in Figures 5 to '7 the lips 22 at the opposite ends of the spring are on alternate sides thereof whereas in the modification shown in Figure 8 the long leaf generally designated 24 has the in-turned lips 22, 22 extending approximately half way across the width of the leaf at each end thereof, but said lips in this modification are located on the same side of the leaf. It will be apparent to those skilled in the art that in a spring constructed with long leaves similar to that shown in Figure 5, said leaves would be interchangeable and only one design would be required for all such leaves for any given type of spring. The same may be said for a spring utilizing long leaves of the design shown in Figure 8. In this design also the top and bottom long leaves would be interchangeable and only one pattern would be required for any particular spring design.

A-form of end casting suitable for my novel spring arrangement is shown in Figures 3 and 4 wherein it may be observed that said casting comprises the outer wall 26 serving as an abutment for the in-turned lips 22 previously described and the central diverging walls 28 and. 30, said diverging walls being integrally joined with the outer wall 26 by the transverse end walls 32 and 34 and the dividing walls 36 and 38. The diverging walls 28 and 330 meet centrally of the casting and provide an abutment for the in-turned lips 22 as best seen at 4B (Figure 4). These diverging walls thus form a V-like structure the extremity of which is spaced from the wall 26 to form the slots 42, 42, said slots being separated by the dividing walls 36 and 38 and serving to receive the lips 22 of the longest leaves l6, I6 pre-- viously described. The ends of said leaves l6, [6 are seated upon the diverging walls 28 and 30 and when the spring is free of loading, the engagement between these diverging walls 28 and 30 and the long leaves l6, I6 is adjacent the extremity of the leaves as best seenat 44 (Figures 2 and 4) It will be apparent that as the spring is loaded and as the load is increased the bearing will shift from the areas 44 to pointsadjacent the outer edges of said Walls as at 46, 46. It will also be apparent that if the spring is forced solid by overloading until the bands l and i4 engage each other, the elongated lips 22 which I have provided at the ends of each long leaf will still have sufficient bearing within the slots 42, 42 to retain the parts of the spring in assembled relationship. By the arrangement I have devised, the said long leaves are prevented from separating from their engagement with the end casting even though the springs may go solid. By this novel means I have overcome the difiiculty above referred to since the elongated lips 22, 22 provide an abutment against the end walls 26, 26 even when the long leaves have vertical bearing on the end blocks only at the areas 46, 36. This abutment of the long lips against the outer walls 26, 26 and at 40 is made possible even under the extreme conditions of deflection by the overlapping arrangement of the above described lips 22, 22.

It will thus be apparent that I have devised a simple and convenient means for overcoming the difiiculty above mentioned in a manner which makes possible the use of present end castings while at the same time obviating the possibility of the parts becoming accidentally dismantled under extreme deflections.

It is to be understood that I do not wish to be limited by the exact embodiment of the device shown which is merely by way of illustration and? not limitation as various and other forms of the device will of course be apparent to those skilled in the art Without departing from the spirit of the invention or the scope of the claims.

I claim:

1. In a full elliptic spring, top and bottom semielliptic units formed of a plurality of leaves of varying length with central securing bands, end castings having outer walls and central diverging walls forming seating means for certain of said leaves of said units, transverse slots in said casting between said outer walls and said diverging walls, the longest leaves of said units having in-turned lips extending part way across the width thereof and received in said slots in overlapping relationship, said long leaves having abutment with said diverging walls adjacent the outer edges thereof when said spring is free of loading and having abutment adjacent the inner edges thereof when said spring is under heavy loading, said overlapping lips providing substantial abutment against said walls under said heavy loading condition,

2. In a full elliptic spring having top and bottom semi-elliptic units formed of a plurality of leaves of varying length with central securing bands, end castings having outer walls and central diverging walls forming seating means for certain of the leaves of said units, transverse slots in said casting between said outer walls and said diverging walls, the longest leaves of said units having in-turned lips extending part way across the width thereof and received in said slots in over-lapping relationship, said long leaves having abutment with said diverging walls adjacent the outer edges thereof when said spring is free of loading and having abutment adjacent the inner edges thereof when said spring is under maximum loading.

3. In a full elliptic spring, top and bottom semielliptic units each comprising a plurality of leaves of varying length and a band retaining said leaves in assembly, certain leaves of respective units having end lips in over-lapping relationship laterally of said spring, end castings having central diverging walls, and vertical outer walls with transverse slots between said outer walls and said central walls, whereby said lips may have substantial abutment against said walls when said spring is under maximum deflection.

4. In a full elliptic spring, top and bottom semi-elliptic units each comprising a plurality of leaves of varying length and a band retaining said leaves in assembly, end castings having central diverging walls, and a vertical outer wall with transverse slots between said end wall and said central walls, each of the longest leaves of said 'units having in-turned lips at the ends thereof, said in-turned lips being formed at the same side of said leaf and extending only part way there-across, whereby the lips of the leaves of the top and bottom units may be received in said slots in over-lapping relationship on assembly of said spring.

5. In a full elliptic spring, top and bottom semi-elliptic units each comprising a plurality of leaves of varying length and a band retaining said leaves in assembly, end castings having central diverging walls, and a vertical outer wall with transverse slots between said outer wall and said central walls, each of the longest leaves having in-turned lips extending part way across the ends thereof and alternately arranged on said ends, said lips being received in said slots in over-lapping relationship on assembly with said castings.

6. A full elliptic spring comprising top and bottom semi-elliptic units, each unit comprising a plurality of leaves of varying length and a band retaining said leaves in assembly, the longest of said leaves having in-turned lips extending approximately half across the width of said leaves, whereby said lips may lie in over-lapping relationship upon assembly of said semi-elliptic units to form said full elliptic spring.

'7. A full elliptic spring comprising topand bottom semi-elliptic units with leaves, each unit comprising a plurality of leaves of varying length and a band retaining said leaves in assembly, end castings having slots, the longest of said leaves having in-turned lips extending only partway across the width of said leaves, whereby said lips may be received in said slots in over-lapping relationship.

8. In a full elliptic spring with top and bottom units having a plurality of leaves banded in assembly, end castings with transverse slots, each of the longest leaves having alternately arranged on the ends thereof iii-turned lips extending part way there-across, the lips of leaves of respective units being received in said slots in over-lapping relationship.

9. In a full elliptic spring with top and bottom units having a plurality of leaves banded in assembly, end castings with transverse slots, each of the longest leaves of said units having inturned lips extending part way there-across and on the same side thereof, the lips of top and bottom leaves being received in said slots in overlapping relationship.

10. In a full elliptic spring with top and bottom units having a plurality of leaves handed in assemb-ly, end castings with transverse slots, the longest leaf of each unit having at its opposite ends in-turned lips extending halfway thereacross, the lips of said long leaves of respective units being received in said slots in over-lapping relationship laterally of said spring.

11. In a full elliptic spring, similar top and bottom semi-elliptic units each comprising a long leaf having at its ends in-turned lips, and end castings having slots for the reception of said lips, each of said slots receiving the lips of topand bottom leaves respectively in over-lapping relationship, whereby a portion of the Width of each slot is occupied by thelip of a top spring and the remainder thereof by the lip of a bottom spring.

12. In a full elliptic spring with top and bottom units having a plurality of leaves banded in assembly, end castings with transverse slots, the longest leaves of said respective units having inturned retaining lips received in said slots in over-lapping relationship late-rally of said slots whereby the effective length of said lips may be increased. 7

WALTER H. BASELT. 

